Abstract
With its wide application in automation, DCS system not only serves as control and operation system, to a large extent but also the integrates operation and productiobn data of other support system makes these data available to operators and managers. Therefore, the issue how DCS system processes data exchanges with third-party system is arousing more and more attention among users. Fieldbus as a new technologies which is precisely in response to this situation.The research project is inspired by one of actual project from Zhejiang University. It illustrates communication between SUPCON JX-300XP and Siemens s7-300 and the overall structure of the system, focusing on the hardware structure, operating principles and software configuration of XP239-DP structure. At the same time, Siemens S7-300 PLC CPU315-2DP is introduced in detail. The aim is to achieve communications between the DCS and Siemens equipment through profibus-dp ,so as to display PLC data in a DCS, and to set up a small part of the parameters.Therefor,it can help the manufacturers to reduce costs and improve the distribution, reliability and scalability.